Minecraft 2D Map Designer (X,Z)

Pen (P)
Erase (E)
Line (L)
Circle (C)
Fill (F)
Select (S)
Share will encode current map to URL hash. Shortcuts: P/E/L/C/F/S, Space to toggle draw, Delete to erase selection.
Tip: click-hold-drag to draw; shift for straight lines; mousewheel to zoom; middle mouse pan.
Pos: x=0 z=0 | Layer Y=64 | Tool=Pen | Zoom=1